Mixed carbonate-carbamate polyesters and process of making



United States Patent ice 3,215,668 MIXED CARBONATE-CARBAMATE POLYESTERSAND PROCESS OF MAKING William E. Bissinger, Akron, Franklin Strain,Barberton, and Henry C. Stevens and William R. Dial, Akron, Ohio, andRaymond S. Chisholm, Pittsburgh, Pa., assignors to Pittsburgh PlateGlass Company, Pittsburgh, Pa., a corporation of Pennsylvania NoDrawing. Continuation of applications Ser. No. 698,055, Nov. 22, 1957,and Ser. No. 113,628, May 31, 1961. This application Apr. 9, 1962, Ser.No. 185,796

23 Claims. (Cl. 260-47) This application is a continuation ofapplication Serial No. 698,055, filed November 22, 1957, and applicationSerial No. 113,628, filed May 31, 1961.

This invention relates to novel types of synthetic resins and to thepreparation of these materials. According to this invention, syntheticresins of unusual toughness and high molecular weight have beenobtained. A large portion of the resins herein contemplated arethermosetting in addition to having the high toughness and molecularweight characterizing all of these resins. Such thermosetting resinshave little or no solubility in organic solvents and resist melting orremain substantially unmelted when heated to temperatures above 100 C.,for example, 110 C. to 200 C. Other resins contemplated herein arethermoplastic and can be formed under heat and/ or pressure. Such resinsalso are characterized by their toughness, good electrical properties,and other advantageous properties.

According to this invention, novel resinous polycarbonate esters of analkylidene bis phenol which contain carbamate or amide groups have beenproduced. Some of these resins contain the general structure:

3,215,668 Patented Nov. 2, 1965 even as high as 50 equivalents of thedihydroxy compound are used per equivalent of diamine.

The type of resin obtained depends upon the manner by which the reactionis conducted. Since the amine normally is more reactive than the hydroxycompound (bisphenol or glycol), the amine normally reacts to a greaterdegree than the hydroxy compound when the bis-phenol chloroformate isadded to a mixture of the two. In such a case, the resin obtained is inessence two resinous esters (block polymers) linked together, the onebeing a polymeric ester of the bis phenol and the theoretical carbamicacid mentioned above, the other being the polycarbonate of thebis-phenol and the hydroxy compound. Such a resin consists essentiallyof blocks or chains of the two types of polymeric esters. A similar typeof material is obtained when the diamine is mixed first with thepolychloroformate of the bis phenol, and the dihydroxy compound addedlater.

A more regular alternation of carbonate and carbamate groups in thechain can be achieved by separately adding the diamine and thebis-chloroformate compound to a pool of the dihydroxy compoundcontaining the hydrogen chloride acceptor, each being added at arelatively slow and controlled rate. Thus, the amine and thebis-chloroformate may be added to a pool of the chloroformate atrelative rates proportional to the total moles of chloroformate, hydroxycompound, and amine to be used. For

example, if one mole of diamine and one mole of dihydroxy compound areto be reacted with 2.2 moles of the bis-phenol bis-chloroformate, a poolof the dihydroxy compound and an excess of hydrogen halide acceptor, forexample, 5.5 moles of aqueous sodium hydroxide, sodium carbonate orbicarbonate, is established. Thereafter, the one mole of diamine and 2.2moles of bis:

where X is the link or linking radical between a pair of phenylradicals, Y is the link or linking radical between the nitrogens, suchas the radical of a diamine. Thus, it will be seen that the polymer is amixed polymer ester of (A) bis-phenol and (B) carbonic acid, and thetheoretical bis-carbamic acid having the structure:

H H H0]JNYN(|TJ0H 0 0 Y being the linking radical between the carbamicacid groups.

The ratio of the carbamate groups to the carbonic groups should be suchthat the carbonic groups are substantially in excess. Normally, thenumber of carbonic groups are at least about twice the number ofcarbamate groups and may be as high as 20 or even 50 times the number ofcarbamate groups.

The carbamate-carbonate esters of the alkylidene bis phenol may beprepared in various ways. For example, a his chloroformate of abis-phenol may be reacted with a diamine and a dihydroxy compound whichcontains two hydroxy groups capable of reacting with chloroformate toform carbonate esters. In this case, about2 to 20 or Example I Thebis-chloroformate of bis-phenol A (a condensation product of acetone andphenol, otherwise known as p,p-isopropylidene-diphenol, see Merck Index,6th edition) is prepared as follows:

Two hundred grams of phosgene is dissolved in 2000 cubic centimeters oftoluene at 5 C. Then, 228 grams of bis-phenol A in 1000 cubiccentimeters of dioxane is added, followed by the addition of a solutionof 242 grams of dimethyl aniline in 240 cubic centimeters of dioxane.During the addition of the dimethyl aniline solution, the temperaturerises to 47 C. Then heat is finally applied to raise the temperature to85 C. for

three hours, The mixture is allowed to stand overnight.

Two liquid phases are thus produced. The lower-dimethyl anilinehydrochloride phase solidifies and is filtered off. The filtrate istopped at reduced pressure at 50 C., first at millimeters and then at 1millimeter absolute pressure, until nomore solvent is collected. The

solid bis-chloroformate of bis-phenol A is thus produced. This materialis purified by recrystallization from ethylene chloride.

A sodium phenate solution is prepared by mixing one mole of bis-phenol Awith 500 grams of sodium hydroxide as an aqueous solution of sodiumhydroxide containing percent by weight of NaOH and 600 milliliters ofmethylene chloride at a temperature of 25 C. to 30 C. One mole ofp,p'diaminodiphenylmethane and 600 milliliters of methylene chloride isadded to this solution.

Thereupon, 3.5 moles of bis-phenol A bis-chloroformate in -00milliliters of methylene chloride is added to the mixture whilemaintaining the temperature at about 25 C. to 30 C. The resultantviscous, white reaction mixture is stirred for an additional hour afteraddition of the chloroformate has been completed, and the mixture isallowed to stand for 14 hours. The reaction mixture is diluted with 5000milliliters of methylene chloride and washed thoroughly with six5000-milliliter portions of water in a separating funnel. The mixture isthen washed with an aqueous solution which contains 3 percent by weightof pyridine and 2 percent by weight of NaOH. Thereafter, it is Washed toneutrality with a dilute aqueous hydrochloric acid solution .andthereafter Washed with water. The solvent is evaporated and a viscous,resinous, solid polymer is obtained.

Example II The process of Example I is performed using the samematerials except that the procedure of adding the reactants isdilferent. In this example, separate streams of the bis-phenol Achloroformate and the p,p'-diaminodiphenylmethane are added gradually tothe methylene chloride solution containing the sodium phenate of thebis-phenol (the reaction product of the bis phenol and the sodiumhydroxide). The rates of addition of the chloroformate solution and theamine solution are so proportioned that the entire amounts of eachmaterial are added during the same period of time. That is, the numberof millimoles of chloroformate introduced into the solution per minuteis approximately 3.5 times the number of millimoles of amine introducedper minute therein.

Example III The process of Example II is performed using one mole ofhexamethylene diamine in lieu of p,p'-diaminodiphenylmethane,

Example IV The process of Example II is followed except that 1.8 molesof bis-phenol A and 0.2 mole of the p,p'-diaminodiphenylmethane is usedin lieu of the amount set forth in Example I.

The above processes produce tough resins which can be molded attemperatures in the range of 150 C. to 200 C. under pressure.

When 0.1 to 1 mole (for example, 0.5 mole) of 4,4'- diisocyanate 3,3dimethyl biphenyl (commercially known as TODI) or like diisocyanate isintimately mixed with any of these resins and the mixture molded at 200C. and held at 200 C. for 30 minutes, clear, tough, insoluble,essentially infusible polymers are produced.

The above are typical examples of the manner in which the resins hereincontemplated may be prepared. Various alkylidene bis phenols can be usedin equivalent amount in lieu of bis-phenol A in the above examples.These include:

(4,4-dihydroxy-diphenyl)methane 1 1- (4,4'-dihydroxy-diphenylcyclohexane 2,2-methylene bis(4-methyl-6-tertiary butyl phenol)2,2'-methylene bis(4-ethyl-6-tertiary butyl phenol) 4,4'-butylidenebis(3-methyl-6-tertiary butyl phenol) 4,4'-thiobis( 3-methyl-6-tertiarybutyl phenol) 1,1-(4,4'-dihydroxy-3,3'dimethyl-diphenyl)cyclohexane 4-2,2- 2,2dihydroxy-4,4'-di-tert-butyl-diphenyl) propane 3 ,4-(4,4'-dihydroxy-diphenyl hexane1,1-(4,4-dihydroxy-diphenyl)-1-phenyl-ethane 2,2-4,4'-dihydroxy-diphenyl) butane 2,2- 4,4'-dihydroxy-diphenyl pentane 3,3 4,4-dihydroxy-diphenyl pentane 2,2- 4,4'-dihydroxy-diphenyl3-methyl-butane 2,2'- (4,4-dihydroxy-diphenyl hexane 2,2-4,4'-dihydroxy-diphenyl 4-methyl-pentane 2,2'- 4,4'-dihydroxy-diphenylheptane 4,4- 4,4-dihydroxy-diphenyl heptane 2,2-(4,4'-dihydroxy-diphenyl tridecane 2,2-bis 3 ,5 -dichloro-4-hydroxyphenyl) propane 2,2-bis (tetrachloro hydroxy phenyl propane 2,2-bis3-chloro-4-hydroxy phenyl propane Moreover, the correspondingbis-chloroformates of these bis-phenols may be used in equivalent amountin lieu of bis-phenol A bis chloroformate.

In addition, various other diamines can be used in lieu of the amines ofthe above examples, also in equivalent amount. Of particular interestare the amines which contain the group where X is a radiacal, such as:O, S, the group or a hydrocarbon radical or substituted divalenthydrocarbon radical which rarely contains more than 8 carbon atomslinking the two aniline groups eee together. Some of these materials areprepared, as is understood by the art, by condensing aniline with analdehyde, such as formaldehyde, acrolein, butryaldehyde, and likealdehydes containing up to about 8 carbon atoms, or a ketone such asacetone, methyl ethyl ketone, or like ketones containing up to about 8carbon atoms. Some of these compounds are in monomeric form, others arein more complex polymeric form but contain two or more imino or aminogroups.

Other diamines which can be used in lieu of amines used in Examples I toIV include the aliphatic diamines, such as ethylene diamine,hexamethylene diamine, propylene diamine, trimethylene diamine,tctramethylene diamine, 4,4'- diamino-dicyclohexyl methane, bis(w-aminoalkyl) sulphides, 2,4-diamino tetrahydrofurane, 1,4-diarninocyclohexane, as Well as the aromatic diamines, such as o-phenylenediamine, 4,4'-diamino diphenyl ether, 4,4- diamino benzophenone,1,7-naphthylene diamine, piperazine, m-phenylene diamine, o-tolidine,m-tolidine, and the like.

Various dihydroxy compounds can be used in lieu of a portion of thebis-phenol A listed above. These include the various bis-phenolsmentioned above as well as the various other dihydric alcohols orhydroxy compounds containing esterifiable hydroxy groups, such asethylene glycol, diethylene glycol, triethylene glycol, tetraethyleneglycol, propylene glycol, 1,3-propane diol, 1,4-butane diol, phthallylalcohol, 1-butene-3,4-diol, 1,4-butene diol, resorcinol, catechol,thiodiglycol, and the like.

According to a further method of producing a resin of the typecontemplated above, an alkylidene bis phenol, such as bis-phenol A, maybe reacted in part With phosgene in the presence of a hydrogen chlorideacceptor, such as an alkali metal or alkaline earth metal hydroxide,carbonate or bicarbonate, or an amine, and usually in the presence ofhalogenated hydrocarbon solvent, such as methylene dichloride. Thisresults in the production of a polycarbonate of relatively low molecularweight havingfree chloroformate groups. Thereafter, a diamine, such asone of the diamines listed above, with or without more bis-phenol, maybe added and the mixture allowed to stand or is heated until furtherreaction has taken place. The amount of diamine thus added can be up toone mole (usually not over 0.5 mole) of the diamine per mole ofchloroformate ooo1 ll in the product.

The following is a typical example of the process herein contemplatedExample V Two thousand, one hundred milliliters of deionized water, 5.28moles of sodium hydroxide, and 1.805 moles of bis-phenol A are placed ina flask. To this mixture is added 1350 milliliters of methylenechloride. The mixture is held at a temperature of 25 C. and 2.2 moles ofphosgene is introduced at a constant rate over a period of about 3.25hours while maintaining the temperature at about 25 C. The chloroformatechlorine content of the'resu'lting resin is about 2.5 percent and theproduct thus corresponds to an average molecular weight of approximately2900. To a portion of the solution containing 100 grams of the resultingresin is added 0.02 mole of ethylene diamine.

The resulting reaction mixture is then allowed to stand at 25 C. withstirring for a period of about 5 hours, and is heated at refluxtemperature for 3 hours. Thereafter, the organic phase is recovered,washed with water to remove entrained salts, and the resulting solutionis heated to evaporate the solvent. The resulting product is a powderwhich can be molded at 200 C. and at a pressure of 2000 pounds persquare inch to produce a tough polymer. Films cast from a methylenechloride solution of the polymer are colorless, clear, and strong.

It is to be understood that the process set forth in Example V can beperformed using various other amines in equivalent amounts in lieu ofethylene diamine. The amines and dihydroxy compounds which may be usedare those listed above.

According to a further method, a mixture of the hisphenol, such asbis-phenol A, with a diamine, such as methylene bis-aniline orhexamethylene diamine, may be reacted with a bis-chloroformate ofanother dihydric compound. Typical bis-chloroformates suitable for thispurpose include the bis-chloroformates of the alkylene glycols, such asethylene glycol bis-chloroformate, diethylene glycol bis-chloroformate,triethylene glycol bischloroformate, tetraethylene glycolbis-chloroformate, 1,4-butane diol bis-chloroformate, resorcinolbis-chloroformate, phthallyl alcohol bis-chloroformate or the like. Thereaction is usually conducted in the presence of an acid acceptor, suchas an alkali metal hydroxide or carbonate.

Here, again, the type of resin produced depends upon the order ofaddition of the reactants, a block type of polymer of the type discussedabove being obtained when the amine is first reacted with thechloroformate as in Example I, and a more regular alternation ofcarbamate and carbonate groups being obtained when thebis-chloroforrnate and the amine are added to the pool of the sodiumphenate as in Example II.

The following are typical examples:

Example VI A mixture of 1 mole of bis-phenol A, 1 mole of methylene bisaniline hydrochloride, 2.2 moles of diethylene glycol bis-chloroformate,and 3000 grams of methylene dichloride is placed in a flask and 7.5moles of sodium hydroxide as an aqueous solution containing 50 percentby weight of NaOH is added while holding the mixture at 5 C. The productis allowed to stand at 25 C. for 4 hours and is recovered by washingwith water and evaporating the solvent. The resulting product is aresinous material which, on molding at C. under a pressure of 2000pounds per square inch, forms a tough molding. When heated with 5percent by weight of toluene-2,4-diisocyan'ate under pressure of 1000pounds per square inch at a temperature of 200 C., an infusible polymeris obtained.

Example VII The process of Example V1 is performed using 1 mole ofhexamethylene diamine in lieu of methylene bis-aniline.

Example VIII One mole of bis-phenol A is mixed with 5.5 moles of anaqueous solution of sodium hydroxide (containing 10 percent by weight ofNaOH) and 600 milliliters of methylene chloride. The mixture is held ata temperature of 25 C. to 30 C. while 2.2 moles of diethylene glycolbis-chloroformate and 1 mole of p,p'-diaminodiphenylmethane dissolved in600 milliliters of methylene chloride are separately added theretosimultaneously over the same period of time. The mixture is recovered asin Example I.

A tough resin is obtained which cures to an infusible state when mixedwith 1,5-naphthalene diisocyanate, the mixture molded and heated at 200C. for 3 hours at a pressure of 2000 pounds per square inch.

Any of the other amines listed above may be used in equivalent amount inlieu of those mentioned in Examples VI and VIII. Bis-phenol A may bereplaced in equivalent amount by other bis-phenols listed above andother bis-chloroformates, such as ethylene bischloroformate, 1,4-butanediol bis-chloroformate, etc., including those listed above, may replaceequivalent amounts of diethylene glycol bis-chloroformate in the EX-amples VI to VIII.

As shown above, the various carbonate polymers which contain carbamategroups such as described above are fusible and soluble in organicsolvents. This is an advantageous property during the period duringwhich the resin is under preparation and/or processing for use.

These polymers can be converted to a state where they are essentiallyinsoluble in inorganic solvents and where they are essentiallyinfusible, or at least do not readily fuse at temperatures below theirdecomposition temperature, :by mixing the polymer described above withan organic diisocyanate. Typical diisocyanates which may be used forthis purpose include 1,5-naphthalene diisocyanate, tolylenediisocyanate, ethylene diisocyanate, trimethylene diisocyanate,tetramethylene diisocyanate, hexamethylene diisocyanate, decamethylenediisocyanate, heptylidene diisocyanate, and the correspondingdiisothiocyanates; cycloalkylene diisocyanates and diisothiocyanates,e.g. cyclopentylene diisocyanate, cyclohexylene diisocyanate; aromaticdiisocyanates and diisothiocyanates, e.g. sin-phenylene diisocyanate,naphthalene diisocyanate, and di-phenyl- 4,4-diisocyanate;aliphatic-aromatic diisocyanates and diisothiocyanates, e. g.xylene-1,4-diisocyanate, 4,4'-diphenylene-methane diisocyanate, andcyclopentyl diisocyanate; and diisocyanates and diisothiocyanatescontaining hetero atoms.

The preferred diisocyanates and diisothiocyanates are of the typeOCNRNCO and SCNRNCS, wherein R represents saturated divalent hydrocarbonradicals with /a chain length of at least two (rarely more than 12)carbon atoms.

The amount of the isocyanate so added normally ranges between about 0.1to 1 mole of isocyanate groups per mole of reactive hydrogen such aspresent in carbamate and hydroxyl groups of the polycarbonate polymersubjected to treatment. The isocyanate may be incorporated by grindingor otherwise pulverizing the polymer and incorporating the isocyanate.Alternatively, the isocyanate may be added to the organic solution priorto evaporation of the solution. In such a case, however,

the evaporation of the solvent should be conducted at a relatively lowtemperature, for example, 50 C. or lower.

At all events,-the desired cured polymer is prepared by heating thepolycarbonate-carbamate mixture with the diisocyanate at an elevatedtemperature, usually above 75 C. and rarely above 300 C. The resultingproducts retain to a large degree the inherent toughness of thepolycarbonate subjected to treatment and at the same time exhibit littletendency to fuse upon heating. They are either inert to organic solventsor are only swelled by such solvents.

The various resins which have been described above can be used for manypurposes. For example, they may be used to provide laminated articles.Thus, the resins herein contemplated can be used to impregnate woven orfelted fiber glass, linen or cotton cloth or the like, and theimpregnated fabric may be built up into a laminate which may then beheated at the fusion temperature of the resin to bond the layerstogether. These laminates can be used as structural material forroofing, siding and other con struction materials for buildings, boats,etc.

Where diisocyanate is included in the nitrogenouscontaining polymersdescribed above, the resulting laminate is quite rigid and shows littletendency to distort at temperatures of 125 to 150 C.

The various resins herein contemplated may be applied to metal as acoating which may be either in the form of solutions or in the form of apowder which is melted or fused onto the metal surface. Many of theproducts herein contemplated have unusually high dielectric strength atelevated temperatures and may be used for electrical purposes aselectrical insulation materials. Thus, they can be molded to enclose andprotect electrical conductors, connections, switches and the like. Sincethe products are clear and tough, they may be used for transparentwindows. They may also be drawn into fibers for use in fabrics.Substantially, all of these materials form very tough, impermeablefilms.

Hence, they may be used to produce films suitable for use in wrappingfood and other articles and for other purposes Where films ofpolyethylene and regenerated cellulose are used.

Although the present invention has been described with reference to thespecific details of certain embodiments, it is not intended that suchdetails shall be regarded as limitations upon the scope of the inventionexcept insofar as included in the accompanying claims.

What is claimed:

1. A mixed carbonate-carbamate polyester of (A) a bis-phenol, (B)carbonic acid, and (C) a diamine.

2. A thermoplastic substantially linear polycarbonatepolycarbamate ofthe general structure:

II II 0 0 where X is the linking radical between a pair of phenylradicals of a bis-phenol and Y is a linking radical between thenitrogens of a diamine.

3. A mixed carbonate-carbamate polyester of (A) a bis-phenol, (B) analiphatic dihydric alcohol, (C) carbonic acid, and (D) a diamine, havingat least two carbonate groups per carbamate group.

4. A mixed carbonate-carbamate polyester of (A) a ldihydroxy aromaticcompound having a pair of phenolic hydroxyls, (B) carbonic acid, and (C)a diamine, the ratio of carbonic groups to carbamate groups being atleast 2 to 1.

5. A polycarbonate-carbamate of (A) an alkylidene bis-phenol, (B)carbonic acid, and (C) a diamine, the ratio of carbonic groups tocarbamate groups thereof being at least 2 to l.

6. The product of claim 5 wherein the alkylidene bis-phenol isp,p-isopropylidene-diphenol.

7. The product of claim 5 wherein the diamine is a condensation productof an aldehyde and aniline.

8. The method of preparing a resinous product which comprises heatingtogether a diisocyanate and a carbamate-carbonate polyester of (A) abis-phenol, (B) carbonic acid, and (C) a diamine, wherein the ratio ofcarbonic acid groups to carbamic groups is at least 2 to l.

9. A method of preparing a resin which comprises reacting a bis-phenolwith phosgene in the presence of an hydrogen chloride acceptor until apolycarbonate containing chloroformate has been produced, and reactingsaid polycarbonate with a diamine.

10. The method of claim 9 wherein the diamine is a condensation productof an aldehyde and aniline.

11. A method of preparing a resin which comprises contacting underreactive conditions a bis-chloroformate of an aliphatic dihydroxycompound, which contains a pair of alcoholic -OH groups, with a mixtureof at least two equivalents of a bis-phenol per equivalent of adiamine.

12. The process of claim 11 wherein the bis-chloroformate is diethyleneglycol bis-chlorofor-mate.

13. A method of preparing a resinous product which comprises heatingtogether a diisocyanate and a carbamate-carbonate polyester of (A) abis-phenol, (B) carbonic acid, and (C) a diamine.

14. A reaction product of a diisocyanate and a mixed carbonate-carbamatepolyester of (A) a bis-phenol, (B) carbonic acid, and (C) a diamine.

15. The product of claim 1 wherein said diamine is piperazine.

16. The polycarbonate-carbamate of claim 5 wherein said diamine ispiperazine.

17. The method of claim 9 wherein the diamine is piperazine.

18. A thermoplastic polycarbonate-polycarbamate polyester comprisingrepeating units of the formula:

wherein Y is the linking radical between the nitrogens of a diamine andX is the linking radical between a pair of phenyl radicals of abis-phenol.

19. A thermoplastic polycarbonate-polycarbamate polyester comprisingrepeating units of the formula:

and

wherein Y is a divalent hydrocarbon radical and X is the linking radicalbetween a pair of phenyl radicals of a bis-phenol.

20. The product of claim 18 wherein the polyester contains at lea-st twoi 9 10 groups per 23. A thermoplastic substantially linear mixed carbon-I ate-carbamate polyester of (A) a bis-phenol, (B) car- -((lfN-7 bonicacid, and (C) a diamine.

0 g p References Cited by the Examiner 21. The reaction product of adiisocyanate and the UNITED STATES PATENTS polycarbonate-polycarbamateof claim 18.

22. A thermoplastic polycarbonate-polycarbamate polyi s; 2 2 u mercompnslng repeating units 01. the formula. 2,799,694 7/57 Ross et a1-o-X o -ir-Y-1' -c o- FOREIGN PATENTS 0 532,543 10/54 Belgium.

546,375 3/56 Belgium.

OTHER REFERENCES and 0 X0 0 o 0 R o o Q g Ser. No. 341,307, Schlack(A.P.C.), published Apr.

wherein Y is the linking radical between the nltrogens WILLIAM H. SHORTPrimary Examiner.

of a diamine, X is the linking radical between a pair of phenyl radicalsof a bis-phenol and R is the radical HAROLD N. BURSTEIN, PHILIP E.MANGAN,

Examiners.

of a dihydroxy compound.

1. A MIXED CARBONATE-CARBAMATE POLYESTER OF (A) A BIS-PHENOL, (B)CARBONIC ACID, AND (C) A DIAMINE.